[HWYSTR455]

How are you going to use the car, and what is the power level?

I've seen a number of local shops butcher rears shortening and modifying them. A professional rear shop that stand behind their' work is the best to use for something like that, say Moser or similar. You're for sure going to get a 'true' rear and quality work.

By the time you get a housing worked, tubes welded, shortened, big bearing flanges, etc, you're at the cost of a new housing anyway.

20 - 30 lbs of unsprung weight isn't something to shake a stick at. There's parasitic loss too, the beefier the rear, the more loss.

Have to consider the body too, 1st gen f-bodies don't have too much room under there, and in a number of options no way can you run a transvers muffler, and sometime no rear sway bar either.

Wheel options become a factor too if you don't have a 'standard' width rear. Add discs and it adds width too. If you have one made, you can compensate. Bolt in axles eliminate brake kick back, and big bearings take way more load, both great options.

I say a Moser 12-bolt is hard to beat for a 1st gen f-body, unless you have big power and focus on drag racing. A 12-bolt Moser housing built to order, is about 1200-1400 with options, and you can spend more than that having a used one worked.

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